The present invention relates generally to disc drive data storage systems. More particularly, the present invention relates to the treatment of the air-bearing surface of a disc drive slider.
A typical disc drive data storage system can include multiple magnetic discs mounted for rotation on a hub or spindle. A spindle motor causes the discs to spin and the surface of the discs to pass under respective head-gimbal assemblies. The head-gimbal assemblies carry transducers which write information to, and read information from the disc surfaces. An actuator mechanism moves the head-gimbal assemblies from track to track across surfaces of the discs under control of electronic circuitry. Read and write operations are performed through read and write transducers which are located at the trailing edge face of the slider. In some disc drives, the read transducer includes a magnetoresistive (MR) element whose resistance changes in response to the magnetic fields corresponding to the data stored on the adjacent magnetic disc. The slider and transducer are sometimes collectively referred to as a head, and typically a single head is associated with each disc surface. The heads are selectively moved under the control of electronic circuitry to any one of multiple circular, concentric data tracks on the corresponding disc surface by an actuator device.
Each slider body includes an air-bearing surface (ABS). As the disc rotates the disc drags air beneath the air-bearing surface, which develops a lifting force which causes the head to lift and fly several microinches above the disc surface. The air-bearing surface is typically covered with a protective coating such as diamond-like carbon (DLC). For example, see Grill et al. U.S. Pat. No. 5,159,508 entitled Magnetic Head Slider Having a Protective Coating Thereon.xe2x80x9d As is known in the art, this layer is provided to enhance the tribological performance of the head-disc interface (HDI). In addition, the DLC coating decreases the read/write transducer sensitivity to electrostatic damage and corrosion.
The head-disc interface design is critical to the reliability of magnetic disc drives, and to MR and GMR (giant MR) disc drives in particular. Asperities, nodules and debris are commonly removed from the surface of the discs through post-sputtering processes and buff/wipe/burnishprocesses. Buffing (tape burnishing) processes can be used to cut down on the nodule extrusions and the asperities. Wiping processes can be used to clean up the surface debris after buffing. The air-bearing surface of the slider may also contain particles, asperities, and debris thereon that may cause serious problems regarding thermal asperities and fly-height hits. Also, the MR element can be damaged by triboelectrical charges (electrostatic charges produced by friction). Furthermore, debris may accumulate in the air-bearing surface or pole-tips and cause poor mechanical integration and corrosion issues. However, because of the small size of the slider, it is not feasible to use conventional mechanical buff/ wipe/burnish processes on the air-bearing surface of the slider. Thus there is presently no post-coating treatment of the air-bearing surface after the DLC coating to remove the asperities, nodules and debris from the air-bearing surface.
The present invention provides a solution to this and other problems and offers other advantages over the prior art.
The present invention relates to the treatment of the air-bearing surface of a disc drive slider.
One embodiment of the present invention is directed to an apparatus for treating a surface of a disc drive slider. The apparatus includes means for irradiating the surface of the slider with light while exposing the surface to an oxidizing gas.
Another embodiment of the invention is directed to a method of treating a surface of a disc drive slider. Pursuant to the method, the surface of the slider is irradiated with light while exposing the surface to an oxidizing gas. In an illustrative embodiment, the oxidizing gas employed is ozone gas (O3). In a further illustrative embodiment, ultraviolet (UV) light is used to irradiate the surface of the slider.
Another embodiment of the present invention is directed toward an apparatus for treating a surface of a disc drive slider. The apparatus includes a process chamber, an oxidizing-gas generator and a lamp. The process chamber is adapted to contain the slider. The oxidizing-gas generator is adapted to introduce oxidizing gas into the process chamber. The lamp is disposed in the process chamber and adapted to irradiate the surface of the slider with light. In an illustrative embodiment, the oxidizing-gas generator is an ozone generator and the lamp is a UV lamp.
These and various other features as well as advantages which characterize the present invention will be apparent upon reading of the following detailed description and review of the associated drawings.